In recent years, organic light-emitting display devices have received attention as a next-generation flat display device. The organic light-emitting display devices have excellent characteristics such as self-emission, a wide viewing angle, and a fast response speed.
A typical organic light-emitting device has a structure provided by sequentially forming, on a glass substrate, a transparent electrode made of ITO or the like, an organic layer including a hole transport layer, a light-emitting layer and an electron transport layer, and a reflecting electrode having a low work function. Emitted light is transmitted through the transparent electrode and is taken from the bottom of the glass substrate.
Each layer of the organic light-emitting device has a thickness of several tens to several hundreds of nanometers and is subjected to light interference. The interference is used to increase the efficiency of light emission in colors of blue, green, and red.
For example, JP-A-2003-142277 (Patent Document 1) has disclosed a display in which ITOs have different film thicknesses for different colors of blue, green, and red to increase the efficiency of light emission in the respective colors. JP-A-2001-323277 (Patent Document 2) has disclosed a display in which organic layers having the same function are formed to have different film thicknesses for different colors of emitted light to increase the efficiency of light emission in the respective colors.    Patent Document 1: JP-A-2003-142277    Patent Document 2: JP-A-2000-323277